PT Apex Pro - Protected Li-ion too big?

[teststrips]

I've done a bit of searching for rechargable protected li-ion cells for my Princeton Tec Apex Pro headlamp. I have not yet found a protected cr123 cell that doesn't have some disclaimer that it is longer than a normal cell.

I really want to use protected cells, but I don't think the extra length is going to work in the Apex Pro.

Had anyone found a protected li-ion cell that fits this particular model... can you point me to where you found it?

 

[RGB_LED]

I use AW's Protected 750mAh (http://www.lighthound.com/index.asp?PageAction=VIEWPROD&ProdID=1155) as well as the LifeP04 500mAh R123s and I find that, with the 750mAh batteries, I have to hold down the lid with a bit more force while I screw in the little screw. There are springs at the bottom of the battery compartment and they just appear to compress more than usual - don't know if the pressure I use to close the lid will have a detrimental impact down the road but it closes fine and all of the settings work as advertised.

Personally, I think the design is poor compared to the closure on the 4xAA 'regular' Apex but, that said, the closure still works and I notice that the screw and closure (for lack of better term) are not plastic but metal-reinforced. I have used only rechargeable R123's in my Apex Pro since I bought it and have had no issues.